/*

 * Licensed to the Apache Software Foundation (ASF) under one

 * or more contributor license agreements.  See the NOTICE file

 * distributed with this work for additional information

 * regarding copyright ownership.  The ASF licenses this file

 * to you under the Apache License, Version 2.0 (the

 * "License"); you may not use this file except in compliance

 * with the License.  You may obtain a copy of the License at

 *

 *     http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

package com.bff.gaia.unified.runners.core;



import com.bff.gaia.unified.runners.core.TimerInternals.TimerData;

import com.bff.gaia.unified.runners.core.TimerInternals.TimerDataCoder;

import com.bff.gaia.unified.sdk.coders.Coder;

import com.bff.gaia.unified.sdk.coders.CoderException;

import com.bff.gaia.unified.sdk.coders.IterableCoder;

import com.bff.gaia.unified.sdk.coders.StructuredCoder;

import com.bff.gaia.unified.sdk.transforms.windowing.BoundedWindow;

import com.bff.gaia.unified.sdk.util.WindowedValue;

import com.bff.gaia.unified.sdk.util.WindowedValue.FullWindowedValueCoder;

import com.bff.gaia.unified.vendor.guava.com.google.common.collect.ImmutableList;



import java.io.IOException;

import java.io.InputStream;

import java.io.OutputStream;

import java.util.List;



/** A {@link Coder} for {@link KeyedWorkItem KeyedWorkItems}. */

public class KeyedWorkItemCoder<K, ElemT> extends StructuredCoder<KeyedWorkItem<K, ElemT>> {

  /**

   * Create a new {@link KeyedWorkItemCoder} with the provided key coder, element coder, and window

   * coder.

   */

  public static <K, ElemT> KeyedWorkItemCoder<K, ElemT> of(

      Coder<K> keyCoder, Coder<ElemT> elemCoder, Coder<? extends BoundedWindow> windowCoder) {

    return new KeyedWorkItemCoder<>(keyCoder, elemCoder, windowCoder);

  }



  private final Coder<K> keyCoder;

  private final Coder<ElemT> elemCoder;

  private final Coder<? extends BoundedWindow> windowCoder;

  private final Coder<Iterable<TimerData>> timersCoder;

  private final Coder<Iterable<WindowedValue<ElemT>>> elemsCoder;



  private KeyedWorkItemCoder(

      Coder<K> keyCoder, Coder<ElemT> elemCoder, Coder<? extends BoundedWindow> windowCoder) {

    this.keyCoder = keyCoder;

    this.elemCoder = elemCoder;

    this.windowCoder = windowCoder;

    this.timersCoder = IterableCoder.of(TimerDataCoder.of(windowCoder));

    this.elemsCoder = IterableCoder.of(FullWindowedValueCoder.of(elemCoder, windowCoder));

  }



  public Coder<K> getKeyCoder() {

    return keyCoder;

  }



  public Coder<ElemT> getElementCoder() {

    return elemCoder;

  }



  @Override

  public void encode(KeyedWorkItem<K, ElemT> value, OutputStream outStream)

      throws CoderException, IOException {

    keyCoder.encode(value.key(), outStream);

    timersCoder.encode(value.timersIterable(), outStream);

    elemsCoder.encode(value.elementsIterable(), outStream);

  }



  @Override

  public KeyedWorkItem<K, ElemT> decode(InputStream inStream) throws CoderException, IOException {

    K key = keyCoder.decode(inStream);

    Iterable<TimerData> timers = timersCoder.decode(inStream);

    Iterable<WindowedValue<ElemT>> elems = elemsCoder.decode(inStream);

    return KeyedWorkItems.workItem(key, timers, elems);

  }



  @Override

  public List<? extends Coder<?>> getCoderArguments() {

    return ImmutableList.of(keyCoder, elemCoder, windowCoder);

  }



  @Override

  public void verifyDeterministic() throws Coder.NonDeterministicException {

    keyCoder.verifyDeterministic();

    timersCoder.verifyDeterministic();

    elemsCoder.verifyDeterministic();

  }



  /**

   * {@inheritDoc}.

   *

   * <p>{@link KeyedWorkItemCoder} is not consistent with equals as it can return a {@link

   * KeyedWorkItem} of a type different from the originally encoded type.

   */

  @Override

  public boolean consistentWithEquals() {

    return false;

  }

}